Recoilless gun for lightweight propellant charge



INVENTOR.

SCHECTER c WALTON MUSSER GEORGE Aug. 1, 1961 G SCHECTER ET AL 1 RECOILLESS GUN FOR LIGHTWEIGHT PROPELLANT CHARGE Flled May 8, 1958 George Schecter, Somerton, Pa.,

United States Patent Office 2,994,249: Patented Aug. 1, 1961 RECOILLESS GUN FOR LIGHTWEIGHT PROPELLANT CHARGE and C WaltonMusser, Beverly, Mass., assignors to the United States of America as represented by the Secretary of the Army Filed May 8, 1958, 'Ser. No. 734,065

1 Claim. (Cl. 891.7)

(Granted under Title '35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment of any royalty thereon.

This invention relates to recoilless guns and has for an object to adapt these guns for use with a lighter weight ammunition than has heretofore been possible, especially in such guns of the Kroeger-Musser type disclosed in Us. Patent No. 2,466,714, dated April 12, 1949. Another object is to make a gun of the foregoing type which is adapted for use with lightweight ammunition in either the granular or sheet type disclosed in the prior invention of Schecter and Kroeger, S.N. 619,644, filed October 31, 1956, for Sheet Propellant, now Patent 2,918,005, dated December 22, 1959.

A distinctive feature of a recoilless gun has been its lightness in weight compared with the weight of a recoiling type of gun of the same size. With great reduction in weight, the gun is more easily portable over rough terrain. Heretofore, however, the ammunition for such recoilless gun has been heavy and has required a metal cartridge case regardless of whether the ammunition be of the fixed or separate loading type or else the loss of incompletely burned particles of propelling charge out the rear venturi opening has been larger than should be necessary.

According to this invention, a perforate cylindrical screen is mounted in the gun instead of around the ammunition as a cartridge case and when so located the gun is well adapted for either sheet or granular type of propelling charge with minimum loss of unburned propellant out the rear of the gun. In this way the functions of the cartridge case are performed for all rounds fired in the weapons by the one perforated sleeve installed in the weapon, eliminating the need to provide such a perforated sleeve for each cartridge and, therefore, re ducing the logistical problem.

FIG. 1 shows a cross section of a gun of the Kroeger- Musser type embodying the present inventionv FIG. 2 is a diagrammatic view of the same gun with a different type of non-rotating projectile and ammunition about to be inserted therein.

Referring to the drawing, FIG. 1 shows a recoilless gun having a chamber in which is located the projectile 11. A propelling charge 12 is located within the perforate cylinder indicated in rear of the projectile. The usual breech block 13 contains two venturi openings not shown. The rear of this gun contains the enlarged portion 14 enclosing a space 15 between the perforate cylinder 16 and the enlarged portion 14. Supports 17 are mounted in rear of the perforate cylinder to space it from the enlarged portion 14, these supports 17 are located angularly to one side and not in line with the venturi opening. The propelling charge 12 is either of the separate loading or fixed ammunition type. A feature of the present gun is its adaptability to receive a propelling charge of either the granular type or of the sheet disc used, it should be enclosed preferably in some kind of consumable wrapper such as the silk or nitrated fabric that have been commonly used in order that it may slide easily into the perforate cylinder 16. When the sheet ammunition of the disc type is used, it may or may not have the consumable fabric surrounding it but none is needed inasmuch as several sheets of ammunition in disc form are supported on an arbor, which is a part of that type ammunition. With either type ammunition a perforate arbor 18 is usually enclosed within the propelling charge at its rear end portion for the purpose of providing an igniter charge of black powder or other appropriate material and a suitable primer of either the electric or impact type used. When the sheet disc type ammunition is used, the perforate arbor 18 is of the type which extends substantially through the entire length of the propelling charge for the purpose of assisting in the igniting of type or of the sheet roll type, both types of sheet am- 7 munition having been disclosed in the prior application of Schecter and Kroeger, S.N. 619,644, filed October 31, 1956, for Sheet Propellant, now Patent 2,918,005, dated December 22, 1959.

When granular type separate loading ammunition is more sheets and discs simultaneously than would otherwise be the case. As shown in the drawing, the perforate cylinder 16 extends rearwardly of the chamber 10 and is a part thereof although of slightly larger diameter as shown in order that the projectile may be rammed into its seat.

In FIG. 2 is illustrated diagrammatically the same general type gun about to receive a different type ammunition. A projectile 11a is of the fin-stabilized type having a rearwardly projecting rod 20 at the end of which are stabilizing fins or vanes 21. The propelling charge 12a may be either of the sheet or granular type and in either case is preferably enclosed in a silk or nitrated fabric enclosure for ease of insertion within the perforate cylinder 16. The usual breech block has been omitted solely for the purpose of enabling the ammunition consisting of projectile 11a and its propelling charge to be illustrated close to the gun in the position in which it is when about to be inserted. Any temporary cartridge case or enclosure for shipping purposes is preferably removed before the ammunition in either fixed or separate loading form is to be inserted within the gun. As shown in the drawing the perforations in the cylinder 16 are approximately the size of those shown in the prior art Patent 2,466,714, dated April 12, 1949, FIGS. 2 and 3 as being customary in recoilless guns for the purpose of retaining propellant grains from coming out of the propellant chamber too soon.

An advantage of the present invention is the fact that the gun is adapted for either granular or sheet ammunition without the necessity for a metal cartridge case being used to enclose the propelling charge. Such a gun as the present greatly reduces the difiiculty in supplying it with ammunition inasmuch as it lightens the Weight of the ammunition to nearly one-half the weight of the former propelling charge when that charge had to be enclosed in the usual metal cartridge case.

We claim:

In a recoilless gun of the breech loading type barrel, having a projectile chamber, a propellant chamber in rear of the projectile chamber, means for retaining a projectile and propellant against falling out of the gun by gravity when the gun muzzle is elevated, at third chamber having an outer wall radially outside of and around said propelforward end portion to said gun, support means for a rear end portion of said cylinder extending radially to the outer wall of said third chamber instead of said cylinderbeing fixed to a propellant round as a case therefor, said metal cylinder having longitudinal rows of substantially equally spaced perforations of a size to retain larger particles of burning propellant against entering said third chamber and being ejected rearwardly therethrough whereby said saving in weight in transporting many rounds of caseless and lighter weight propellant rounds may be attainable and of substantial magnitude.

References Cited in the file of this patent UNITED STATES PATENTS 1,274,258 Gerdom July 30, 1918 Cooke June 7, 1921 Kroeger et a1. Apr. 12, 1949 Stover Dec. 6, 1949 Hickman May 27, 1952 Engelke Sept. 15, 1953 FOREIGN PATENTS France June 26, 1926 Great Britain May 29, 1957 

